This leads to all sorts of bogus cruft getting installed on machines by users who are without a clue with computer security, and simply don't know to install tools like NoScript or SiteAdvisor and to pay attention to the warnings they generate.
Linux's in general do not run normal users with superuser capabilities, which stops a lot of garbage from getting installed on machines in the first place.
Ritchie's Law - assume you have screwed something up *first*, before blaming the tool...
"A car is just a big purse on wheels." -- Johanna Reynolds